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Product Code: iDATA_USUR16_MC_PC

Unlike other cancer treatments, brachytherapy has a history that spans over a century. In 1901, Pierre Curie, a physicist from France, first suggested that radiation could be used to treat cancer to one of his colleagues, a doctor named Henri-Alexandre Danlos. Dr. Danlos tested the idea and found that radiation caused tumors to shrink. Early techniques of brachytherapy were first performed at the Curie institute by Dr. Danlos. Over the next fifty years, doctors around the globe (through trial and error) expanded clinical applications of brachytherapy to include cervical, prostate and breast.

Towards the end of the 20th century, brachytherapy received a huge stimulation from imaging technologies such as magnetic resonance imaging (MRI), computer tomography (CT) and ultrasound. This allowed doctors to place the radioactive materials in precise locations in the body. RTi may be broken down into permanent and temporary modalities.

Cryoablation is the use of freezing temperatures to erode and destroy specific tissue cells. What is known as modern cryoablation therapy began in the early 1960s when cryosurgical probes cooled by liquid nitrogen were introduced. In the 1970s, handheld cryoablation devices were developed for cardiac purposes. As time went on, cryoablation has evolved into an exact science. Modern cryoablation can be described in four stages: freeze, thaw, hemorrhage and inflammation and replacement fibrosis. The theory claims that, during the initial phase, the cellular metabolism of the tissue is slowed and the area experiences progressive hypothermia. Once the thaw begins, the tissue experiences cellular damage, which culminates in vascular obliteration and ischemic cellular necrosis. Cryoablation uses compressed argon gas as a coolant. As the gas progresses through the needle, the end of the needle develops an ice ball that is then used to “ablate” the desired tissue.

The market for cryoablation is a little bit different from other ablations. Of all procedures performed in 2015, half of them originated from capital units that were already installed and the other half came from rentals. As such, the cryoablation models in this chapter are split into rentals (which include disposables), disposables used by an existing installed base and the machines themselves. When a hospital needs to perform a cryo procedure that does not own the capital equipment, they can have it dropped off (complete with the disposables) for a fee. For hospitals that do not have the funds or lack a sufficient customer base, this arrangement can be desirable.

Internal radiation therapy (RTi), also known as brachytherapy, is a form or RT that puts the radioactive material inside the patient either via a catheter or a needle. In terms of its placement, RTi may be administered as intracavitary or interstitial. In the case of intracavitary, the radioactive material is placed inside a cavity in the body such as in the rectum or uterus; in the case of interstitial, the radioactive material is placed on/near the cancer but not inside a body cavity. The most common form of brachytherapy involves the placement of “seeds” inside the body involving differing durations and radioactivity. Each seed is approximately the size and shape of a small grain of rice.